feat(web): read admin lanes from the durable pass log, not a poller snapshot (#145)

The Lanes page now projects store.LatestLanePasses and the owner-window
outcomes (store.LanePassOutcomes) into per-Site rows instead of reading an
in-memory Poller snapshot, so a deploy answers the instant the store is up.
Browser configuration is a config fact and reachability is derived from
recent browser-Site passes inside latest.RefuseBackoff.

This atomically deletes the in-memory path in the same commit that makes the
page read the DB: latest/status.go (LaneState, Status, LaneStatus,
recordLaneState) and the web.LaneReporter seam plus fakeLanes are gone, and
latest.refuseBackoff is renamed latest.RefuseBackoff at every callsite.
ownerWindow (#142) is referenced, never declared (contract C2)

backend/AGENTS.md

@@ -252,16 +252,18 @@ keep warning to reinstall on all devices.
   (`view.Owner = readerID == h.store.OwnerID()`): it gates a link, not an
   endpoint, so it is a rendering decision a registration-time wrapper cannot
   express. Do not "unify" it into the gate.
-- Lane figures come through the `web.LaneReporter` seam
-  (`latest.Poller.LaneStatus`), never a table. `main.newRouter` takes the
-  reporter as an interface and converts a nil `*Poller` to a nil interface — a
-  typed nil would make the page claim a poller exists.
+- The Lanes page reads the pass log, never a running poller: `lanesView()` in
+  `admin_lanes.go` projects `store.LatestLanePasses()` and
+  `store.LanePassOutcomes()` (ADR-0012), so a restart answers the instant the
+  database is up. Browser configuration is a config fact and reachability is
+  derived from recent browser-Site passes inside `latest.RefuseBackoff` — no
+  reporter interface exists to fake.
 - A pass that returns before computing figures (refusal backoff, sidecar down)
   carries the previous pass's numbers forward rather than recording zeroes.
 - **`Checked` next to `Due` is what separates a stopped Lane from a quiet one**,
   so neither may be dropped from the row.
 - Due-without-Checked is **not** by itself a stall: a browser Lane under both
-  wake thresholds sets `LaneState.Asleep` and renders "browser asleep", and
-  never counts toward `Attention`. That is the commonest healthy state for
-  kagane, comix and novelfull, so spending the stall mark on it would train the
-  owner to ignore the mark that matters.
+  wake thresholds records its pass with the `SkipAsleep` skip and renders
+  "browser asleep", and that never counts toward `Attention`. It is the
+  commonest healthy state for kagane, comix and novelfull, so spending the
+  stall mark on it would train the owner to ignore the mark that matters.